1. FIELD of the Invention
This invention relates to a molding method for continuously performing orientation blow molding from injection molding of a preform made of synthetic resin to a thin-wall hollow molded article.
2. Prior Art
As one of the molding methods generally called injection orientation blow molding, there is a three-station molding method in which a mouth portion of an injection molded preform is held by a lip mold and the preform is immediately transferred to a blow mold for orientation blow molding.
In a molding method of a three-station system disclosed in Japanese Patent Application Laid-Open No. 63-296921, orientation blow molding is carried out after inner and outer temperatures of a preform released at a high temperature are made uniform by internal heat of the preform itself to eliminate a temperature difference therebetween.
A technical idea for releasing a preform at a high temperature is already disclosed in a molding method of a four-station system.